The merger of CVS Health, one of the nation’s largest pharmacy retailers, with third-largest health insurer Aetna has the potential to transform the health care system and raises concerns about the effect the merger could have on drug prices and competition. This would be the first time that a large pharmacy retailer gains control of one of the nation’s largest health insurers. CVS Health not only has 9,800 retail outlets in nearly every state (except Wyoming), but also 94 million members in pharmacy benefit manager CVS/Caremark.

On Wednesday, the U.S. Department of Justice approved the deal on the condition that Aetna sell its Medicare Part D prescription drug plans. CVS’ $69 billion purchase of Aetna is expected to close at the end of the year. “The deal, however, still needs the approval of state regulators, who generally follow the lead of federal antitrust regulators,” according to Bruce Japsen, writing about the deal for Forbes.

“The combination of CVS and Aetna creates an enormous market force that we haven’t seen before, straddling more market sectors and creating new and potentially far-reaching profit-maximizing incentives to undermine competition, Consumers Union senior policy counsel George Slover said in a statement about the CVS-Aetna deal. “Despite the companies’ big promises that consumers will see greater savings thanks to new ‘efficiencies,’ history has taught us to remain skeptical. This type of consolidation in a market already dominated by a few, powerful players, presents the very real possibility of reduced competition that harms consumer choice and quality.”

The AMA also cited concerns about the impact on consumers. “We now urge the DOJ and state antitrust enforcers to monitor the post-merger effects of the Aetna acquisition by CVS Health on highly concentrated markets in pharmaceutical benefit management services, health insurance, retail pharmacy, and specialty pharmacy,” AMA President Barbara L. McAneny, MD, said.

In The Washington Post, Brian Fung reported on how the deal could transform the health care system. “Driving that new approach to care will be the immense amounts of data generated not only by CVS’ 9,800 retail outlets and 1,100 MinuteClinics but also from Aetna’s 22 million medical members. The result could make CVS a destination for more than flu shots and treatment of minor illnesses,” Fung wrote.

After the merger was proposed in December, we covered how the deal could affect the health system. At the time, Japsen noted that the CVS-Aetna merger was one of several deals aimed at getting health insurers into the delivery of care, “as fee-for-service medicine gives way to value-based care that keeps patients out of the hospital.”

Fung hit this same theme in his Wednesday article, explaining that the deal signals a shift in focus from caring for the sick to preventing illness. “Much of the U.S. health-care system revolves around fixing costly ailments,” Fung wrote. “But in trying to head off the worst cases, CVS and Aetna are aiming to become a part of the nation’s social fabric, using the local retail pharmacy as both a window into people’s lives beyond the doctor’s office and assuming the role of a health-care assistant.”

Also, CVS and Aetna could begin to coordinate transportation for patients who otherwise have trouble getting to routine physician and hospital appointments. “That help could extend to nutrition counseling or even the use of wearable devices that automatically notify patients and health-care providers of a potential problem,” Fung explained.

In a news release, CVS Health CEO Larry J. Merlo said, “Our focus will be at the local and community level, taking advantage of our thousands of locations and touch points throughout the country to intervene with consumers to help predict and prevent potential health problems before they occur.” And, of course, Merlo said the combined companies would offer better care at lower cost, a statement that journalists will need to fact-check in the coming years.